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Discussion Starter · #1 ·
I've seen some threads on this board suggesting that it's best to let a progressive capable DVD player just output the interlaced signal direct from the DVD and let the (assumedly) higher quality chips on the TV make the signal progressive again.


But in reading the ultimate (and fascinating) DVD FAQ :

http://www.thedigitalbits.com/officialfaq.html#1.40


… I don't see how the TV can do as good a job as the DVD player. The DVD itself is recorded in interlaced format but it looks to me that it’s easier for the DVD player to reassemble the original progressive scan movie than the TV, since the DVD player has access to a flag in the MPEG2 stream that tells it the source was progressive. When the TV tries the same trick how does it know if the source was progressive or not – or doesn’t it matter?
 

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Read the gory details in this article . Basically, the flags aren't necessary since one can just buffer fields looking for identical ones, detecting the 3:2 cadence and reinterleaving appropriately. The better players don't rely on flags since the flags are incorrect on some disks.


TV's with decent line doublers would make any differences small, but progressive out on the DVD can be slightly sharper on most sets.
 

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Discussion Starter · #3 ·
Wow, awesome article, thanks for the pointer to it Stephen.
 

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Stephen Tu,

Good job linking to the DVD shootout. Best thing out there. OT, but are you a bridge player? Someone with your name used to post on a K-S discussion forum. (If that's meaningless to you, you're not him!)


Mike,

If you go to the home page of that site, you'll find at least two followup studies that they've done since then. It never ends...
 

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A very good article. I've read it before, but I still have a problem with the authors vocablulary. Sometimes it confuses the readers. There are some simple things that folks need to know about the basic concept of the article.


1st. Film is NEITHER interlaced NOR progressive. It is a frame. The ENTIRE PICTURE is present all at one time. When you go to the theater to watch a film, if you were to look at the film to the light you would see a complete frame. The entire picture is shown on the screen all at one time. That is NOT how it is on your televison. Film is a frame that includes the entire picture on it.


Video is done based on the NTSC standard. Interlaced DRAWS the picture in a scanned method in 2 parts. First the odd scan lines; 1,3,5,7,etc... then it goes back and draws the even ones; 2,4,6,8,etc... Progressive on the other hand is just what it sounds like. It draws the scan lines progressively; 1,2,3,4,5,etc...


Film winds up running at 24fps while video does almost 30fps. In order to convert 24fps to a system that does 30fps, you do what is known as 3:2 pulldown. 3:2 pulldown is JUST the conversion of film to video. It is to eliminate jitters. It can be done in the DVD player or in the TV (NEWER TV's That is). It's better to do it in the DVD player because there are less stages to go from beginning to end.


Progressive scan is better in fast action scenes, i.e. sports, because it draws the picture smoother when everything is moving so fast. Progressive however has NOTHING to do with 3:2 pulldown. YES, it so happens that almost every Progressive scan DVD player has 3:2 pulldown capabilities, but that doesn't mean they are the same thing. It's just that it's needed to handle the material on the DVD that was film converted to video. Just because "ALL CARS HAVE TIRES" doesn't mean "EVERYTHING WITH TIRES IS A CAR". 3:2 pulldown and progressive video isn't the same thing. VHS, Laserdisc, OTA is already in Video Mode. If it was a film, it was already converted prior to being stored on tape or received from broadcast.


Most modern TV's also have 3:2 pulldown capabilities. They also have built in scalers to convert Interlaced to progressive. The scalers are to improve the picture to progressive. Especially on the larger screens today. These larger screens really pronouce the interlace signal in fast moving scenes. This is just more technological ways to improve the viewing experience.


I'm not trying to dispute the article. I have just found a number of people who misunderstand the difference between Film and VIdeo. Interlaced and Progressive. 3:2 Pulldown and NOTHING. See my point. We are talking about 3 different things. Film is a complete FRAME. Video isn't . Film is NEITHER linterlaced or progressive. Only video can be. TV was designed to receive a BROADCAST. Signal over the air. It was designed to DRAW the picture on the screen. 3:2 pulldown is the method of CONVERTING one (FILM) to the other (VIDEO)... Later.... Mike....
 

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I don't know, I find the article's terminology more consistent and less confusing than yours ...

Quote:
Film winds up running at 24fps while video does almost 30fps. In order to convert 24fps to a system that does 30fps, you do what is known as 3:2 pulldown. 3:2 pulldown is JUST the conversion of film to video.
More precisely it is how 24 frames of film are distributed onto 60 fields of video.
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It can be done in the DVD player or in the TV (NEWER TV's That is).
Actually the "3:2 pulldown" is done in the telecine converting film to video. The MPEG coding has flags telling the DVD player which fields to repeat to create this 3:2 pattern for interlaced playback. The TV has nothing to do with it. The "it" that can be done in either player or TV is the reversal of this process, "inverse 3:2 pulldown" aka "film mode deinterlacing" aka "inverse telecine". The pattern is detected, the original frames reconstructed, then displayed (also in a 3:2 pattern except now displaying 60 frames/sec rather than fields).

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Progressive however has NOTHING to do with 3:2 pulldown. YES, it so happens that almost every Progressive scan DVD player has 3:2 pulldown capabilities, but that doesn't mean they are the same thing.
No, they aren't the same thing, but I don't see where the article ever implies that. Saying they have nothing to do with each other is erroneous. Detection of the 3:2 pulldown cadence is needed to convert from interlace to progressive scan in the most accurate manner, if the original source was film.
 

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Discussion Starter · #8 ·
So for the purposes of this discussion (which is best)…. It looks to me that if you have a progressive output player there is no reason to let the TV do the de-interlacing.


Since this is a mechanical process rather than black magic like encoding, the quality of the de-interlacer is not in question. It either works or it doesn’t.


Therefore, since the DVD player does not have to do the two additional steps (convert the analog signal back to digital and then back again to analog after de-interlacing) theDVD is likely to produce a superior picture when you let it do the de-interlacing.
 

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It seems to me the answer really depends on the DVD player. If you have a $200 progressive player, it's going to take a lot of shortcuts to get that price point and the deinterlacer (among other things) will suffer, in which case it may be better to have the TV do it.


On the other hand, if you have something like an Arcam, Meridian, or Krell that runs in the 4-figure price range, you should expect that it'll have an excellent deinterlacer, superior to the one in your TV. In that case you'd want to have it send a progressive signal to the TV.


I'm somwhat in the middle with a $900 Marantz progressive. I do use the DVD player to handle deinterlacing rather than my Sammy DLP.


So I would say if you have a cheapy DVD, let the TV do the interlacing. With a high-end DVD player let it do the work. For something in the middle, try both and see what's better. Quality of cable matters too. I decided not to skimp on my component cable and spent $175 on a very good one.


Dean
 

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Quote:
Since this is a mechanical process rather than black magic like encoding, the quality of the de-interlacer is not in question.
Encoding isn't black magic either ...
Quote:
It seems to me the answer really depends on the DVD player. If you have a $200 progressive player, it's going to take a lot of shortcuts to get that price point and the deinterlacer (among other things) will suffer, in which case it may be better to have the TV do it.
This simply isn't true. Look at the results of the various shootouts at that article's host site. The $200 Panasonic players often match or outperform the $8000 boutique players. For deinterlacing this is not surprising whatsoever, since if you look inside the players you will find they are often using the exact same deinterlacing chip despite the 4 figure price difference. This is true for other chips as well. Those Meridian/Krell companies just figure if they dress up the player in some huge fancy box, put their name brand on it, make it heavy & imposing, that some suckers will pay them thousands more for no difference in performance.

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Quality of cable matters too. I decided not to skimp on my component cable and spent $175 on a very good one.
You let yourself get robbed here.
 

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Discussion Starter · #11 ·
Quote:
Originally posted by Stephen Tu
Encoding isn't black magic either ...
I should have said encoding is an art form - some encoders are better than others. De-interlacing however is straight-forward with no excuse to do it badly.
 

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Quote:
Originally posted by dwette
It seems to me the answer really depends on the DVD player. If you have a $200 progressive player, it's going to take a lot of shortcuts to get that price point and the deinterlacer (among other things) will suffer, in which case it may be better to have the TV do it.


On the other hand, if you have something like an Arcam, Meridian, or Krell that runs in the 4-figure price range, you should expect that it'll have an excellent deinterlacer, superior to the one in your TV. In that case you'd want to have it send a progressive signal to the TV.



Dean


That's rich and I have a Land Rover I'd like to sell you. Read the DVD shootout article, I did and bought the Panasonic XP-30 for $164. It's rated at the top above all the big bucks brands. I had 2 other players before this and it is visibly superior, I couldn't be happier with it. Put it in progressive and forget about it.
 

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I wasn't trying to imply that the artcle was saying 3:2 pulldown and progressive were the same. I was saying that many people, and the train of though of some of the previous posts were thinking of the 2 as the same.


I personally prefer to let the DVD player handle the reverse 3:2 process if possible. I think that even the cheaper Progressive scan DVD with 3:2 will do better than the TV. The circuity I think is better, plus there are less steps required in the process. I also prefer to run the DVD player in progressive mode. It helps in fast action video.


There are however still too many members of the jury out yet on the benefits either way. Some people leave their tv in the "Movie Mode", Cinema Mode" or whatever mode utilizes the 3:2 pulldown process. They leave it in this mode for DVD, Satellite, Cable, VHS, and Laserdisc. They sware it makes everything look better than the other modes do. I'm not sure how they come up with this information. I wasn't aware that reversing 3:2 was needed in VHS tapes, Directv and laserdisc. Oh well that's why there are all these products and people to buy them.


I personally, have all of my modes calibrated for different inputs. Movie mode is professionally calibrated for DVD. Sports mode is calibrated for Satellite. BOTH DVD and Satellite are COMPONENT input. I then have another mode calibrated for COMPOSITE inputs such as VHS and LASERDISC. And the forth mode is calibrated for OTA signals. Have a great day.... Later.... Mike.,,...
 

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Quote:
I wasn't aware that reversing 3:2 was needed in VHS tapes, Directv and laserdisc.
Of course it is, for the material that was originally film, including almost all movies and the many TV shows which are shot on film. The doubler detects the 3:2 pattern in the interlaced video coming in, and reassembles the original frames. It's really not any different from DVD here. Why should it be?
 

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Hmmmm, Now you really have me thinking. I know that a lot of DVD material is stored on the disc in 24fps format. That and the digital format therefor makes the 3:2 process a requirement. VHS, Laserdisc, OTA, and Satellite; (Anything NON-HDTV) is however stored or transmitted in an analog and/or processed state already.


In other words, I believe that the 3:2 process and conversion was done PRIOR to the material being stored to Tape, Laserdisc, or transmitted over the air. This therefor does not require the material to have the reverse 3:2 process done again. At least this is what I've been under the impression of. If this is incorrect, please provide some information that I can review please.... Thx.... Mike....
 

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Why has this thread gone hostile? Most of these issues are not subjective. The best settings for DVD playback is, so is the value of an $8000 DVD player, but the processes that make up the technology are not subjective.


Stephen Tu is quick to make personal attacks that have insulted about everyone on this thread (I'm sure I'm next) without offering any more proof of the accurancy of his statements than the next guy. He seems educated about these issues, but his tone robs him of any validity, at least in my mind.


Christcorp was attempting to clear up some potential terminology issues (good post, actually) that the average enthusiast might struggle with, but was apparently not using terminology that pleased everyone. At least he said things like "I believe" when he wasn't sure.


A lot of info in this thread is just wrong but written as scripture. Go look it up. I could say, but who the hell am I? I'm just a guy who's authored a few mass-release DVDs. There's a correct answer for all of this and the web is packed with authoritative sites on the subject.


Bayrider doesn't like his Land Rover.


The bottom line is that none of us know what's best for anyone else. You really can't even say what SHOULD look best because you only know what YOU prefer. I may hate your settings. You may hate mine. And I don't ever want to hear about scientific reviews like the Secrets DVD shootout. Numbers means nothing to me and they should only be used as a guide. Use your eyes and ears.


It's important to theorize, but NEVER insult someone for disliking what you like. And if you're going to throw mud please back it up. I don't believe any one of you unless it makes sense. You shouldn't believe me unless I can either show you proof or give enough info so you can understand for yourself.


The correct answer to the original question, "Progressive or Interlaced out from DVD player - which is best?", is... Try 'em both. Which looks better to you in your living room? It's easy. It's one or the other.


Wow, is this long winded. I must be full of myself.


Bayrider - how much do you want for your Land Rover. That's one sweet ride! My neighbor LOVES his. My other neighbor LOVES his Dodge Stratus. I wonder which one's wrong.
 

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For what it's worth, I've spent thousands and thousands of dollars on cables alone. I've bought components that cost 20 times more than the average components and only a few people can see or hear the difference. Those who aren't able to see or hear these differences believe that I'm "artificially convinced" that the higher cost and reputation are the reason I think there's an improvement when there's really no difference at all. Why should they care? I wasn't going to give them the extra money anyway. I see it or hear it maybe because I'm looking for something they're not. This doesn't mean either one of us is lacking some sort of talent. Be strong! Don't get offended!


Fact is, a $175 set of component cables don't pass the exact same video information as a set that costs $17.50. If you don't see it then you're better off because you get to save a ton of money. Don't criticize those who do.
 

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Quote:
Originally posted by elambo
...And I don't ever want to hear about scientific reviews like the Secrets DVD shootout. Numbers means nothing to me and they should only be used as a guide. Use your eyes and ears....
Very well said. I'm glad someone else around here understands that.


I learned decades ago, that benchmarks and specs are only a small part of the picture and meaningless on their own. In the 80s I worked for a Linn/NAIM dealer (as a record buyer, not an audio salesperson) while I was working on my music degree. At the time I had a McIntosh system worth thousands of dollars. My employer convinced me to take home a $500 20 Watt NAIM integrated amp to compare to the McIntosh system. The NAIM was inferior in every way when it came to specs and numbers, but musically it blew away the McIntosh system in every way. So much so that my McIntosh gear (and a Thorens turntable) was for sale in the paper the next day. Once I had a NAIM system I was enjoying music (Classical and Jazz mostly) like I never had before.


If I had been close-minded to say the NAIM couldn't be better because of benchmarks and specifications I would have missed out on all the joy and excitement I got out of listening to music on the Linn/NAIM system I ended up with.


This gear is only as means to an end. For me the only real judge is eyes and ears. Numbers are mostly meaningless. I never choose between two products based on specs. In fact, I don't even pay attention to them when I read a brochure or a review.


Dean
 

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Discussion Starter · #19 ·
Most people don’t have time to spend figuring out which is the best way to use equipment they have. Some of us may not even know what we are looking for to know whether something is better or not. For instance an overly saturated picture may look good at first, but the picture is incorrectly set. Wherever possible we’d just like some authoritative answer telling us which is likely the best way to go.


I can’t tell any difference between the Progressive out and Interlaced out modes of my DVD player because the Sammy 507 does a good job of taking that interlaced signal and making it progressive. Now if I spent some time and examined many different pictures maybe I could start to see a difference – but I doubt it in this case.


I think the info we’ve seen in this thread suggests that technically the DVD player-outputting Progressive is the way to go. I have seen no evidence that having the DVD player output interlaced could possibly be better.


The answer to the subject question should not be subjective.
 

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Quote:
Hmmmm, Now you really have me thinking. I know that a lot of DVD material is stored on the disc in 24fps format. That and the digital format therefor makes the 3:2 process a requirement. VHS, Laserdisc, OTA, and Satellite; (Anything NON-HDTV) is however stored or transmitted in an analog and/or processed state already.
The requirement for 3:2 pulldown is due to the mismatch between the 24 frames/sec of film and the 60 fields/sec of NTSC video. That's any video, regardless of media. The only difference for DVD vs. the other media related to this is that on the DVD disc itself the repeated fields are usually omitted to save space; instead there is just an instruction to "repeat first field". But the generated output pattern is the same for all.

Quote:
In other words, I believe that the 3:2 process and conversion was done PRIOR to the material being stored to Tape, Laserdisc, or transmitted over the air. This therefor does not require the material to have the reverse 3:2 process done again.
Yes, the 3:2 pulldown is done prior to storage/transmission, in the telecine process. So 24 frames of film have been converted to 60 fields of video, and nothing needs to be done for interlaced display. However, on a progressive scan display, what you need is 60 frames of video, not 60 fields. In order to construct 60 frames from the 60 fields, ideally you want to do it by weaving fields together that were originally part of the same film frame. This preserves resolution (vs. making frames by interpolating between lines of single fields), and avoids artifacts from erroneously combining fields from different frames. In order to do this properly, you need to detect the 3:2 pattern in the video, reverse the process to obtain the original frame, then output the entire frame. (Again in a 3:2 pattern to get from 24 to 60, except with whole frames rather than fields).


This is what you want to do regardless of source, when dealing with film-sourced video.
 
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